Micellar Electrokinetic Chromatographic Analysis of Historic Dyes and Their Photofading Products

Since the early 20th century, the Monroe Chemical Company’s Putnam Fadeless Dyes were used by consumers to dye numerous types of textiles. In this work, we describe a novel micellar electrokinetic chromatographic (MEKC) method employing sodium cholate and acetonitrile in the background electrolyte that can be used to analyze these dyes. Specifically, Putnam Fadeless Dyes were successfully extracted from linen samples colored with them and the components of each dye were separated and detected using MEKC. These results compared favorably to MEKC data from standard dye solutions. Dyed linen samples were also exposed to simulated sunlight and MEKC was used to analyze dyes extracted from them. The resulting data showed that photofading altered the amount of dye in the fabric but not its chemical composition.